At least one embodiment of the inventive technology relates to the control of pests. More particularly, certain embodiments may relate to the control of larvae, subadult and adult ticks on rodents with insecticides. Embodiments may also relate to the control of larvae, subadult and adult ticks or fleas on rodents with insecticides or insect growth regulators in combination with rodenticides (e.g., slow-acting rodenticides) for simultaneous control of ectoparasites and their mammalian hosts. Aspects of the inventive technology also relates to the simultaneous control of rodents and/or cockroaches and rodents and/or ants using insecticides and rodenticides in combinations.
Diet compositions formulated to target rodents are colloquially referred to as “bait” or “rodent bait”. There are many commercially available “rodent baits”—containing poisons lethal to rodents—that are available to consumers and pest control professionals.
Diet compositions that are provided to wild rodents and mammals allow for the oral administration of chemicals including rodenticides, insecticides and/or insect growth regulators to insects, rodents or mammals. Insects, rodents or mammals consume the diet compositions, which contain rodenticides, insecticides and/or insect growth regulators. Oral administration of diet compositions to rodents or other mammals may involve simply placing the diet composition (a broad term that includes what is typically referred to as “bait”) includes the simple act of setting out the composition (e.g., placing it in an area that may be trafficked by the mammal of interest) and the resultant consumption of the composition by an animal (e.g., a host mammal). Such consumption by a host mammal exposes not only the mammal to the ingredients of the composition (e.g., rodenticides, insecticides and/or insect growth regulators in the diet compositions), but also results in the exposure of the blood-feeding ectoparasites of these animals to these ingredients when they take a blood meal from that mammal.
Rodent diet compostions are formulated by many methods that are well known to individuals of ordinary skill in the art. As diet composition vehicles (which are types of inert ingredients, a term generally referring to ingredients that, unlike rodenticides and insecticides, are non-toxic), various grains could be used, including corn, corn meal, oats, barley, peanuts, wheat and grain flours. These inert ingredients are formulated between 95-100%, individually or as mixtures. Grain ingredients may be mixed with powdered sugar and vegetable or mineral oil, both at 0.1-5%. A rodenticide may be added at the desired concentration either as an individual ingredient or mixed with mineral or vegetable oil or as a pre-mix. Likewise, a dye (another inert ingredient) may be added for the purpose of coloring the diet composition a distinct color (0.1-1%). Dye may be added at the desired concentration either as an individual ingredient or mixed with mineral or vegetable oil or as a pre-mix. Ingredients may be mechanically admixed in commercial mixers and packaged for retail use. Any of the inventive methods, apparatus, or compositions of matter disclosed herein may involve an inert ingredient(s) that forms the non-insecticide, non-rodenticide balance of the diet composition.
Rodent diet compositions may also be formulated using the above-described inert ingredients (e.g., grains, flours) in combination with wax (another inert ingredient). The mix can then be extruded through commercial extruders, which melt the wax dispersed within the mix, followed by cooling the wax to form a bar. Wax concentrations may be between 1-95% and various flours or grains are added between 1-95%. The rodenticide may be added at the desired concentration either as an individual ingredient, or mixed with mineral or vegetable oil, or as a pre-mix. Likewise, a dye may be added for the purpose of coloring the diet composition a distinct color (0.1-1%). The dye may be added at the desired concentration either as an individual ingredient or mixed with mineral or vegetable oil, or as a pre-mix. Rodent diet composition bars (or “bait bars” in colloquial language) may then be packaged for commercial use. Compositions of matter (e.g., diet compositions) that relate to the claimed subject matter may possibly also comprise inert ingredients (e.g., grain, wax, coloring, etc.) as described above or as may be well known in the art.
Diet compositions can also be formulated as gels as referenced in U.S. Pat. No. 6,264,969 (Poché) or as described in other prior art. Examples of rodenticides that are employed for rodent control include, warfarin, diphacinone, chlorophacinone, bromethalin and cholecalciferol, sodium fluoroacetate, coumatetralyl, zinc phospide, brodifacoum, bromodialone, difethialone, difenacoum and flocoumafen. Rodenticide concentrations in the diet may be formulated between 0.001% -0.5%, including, but not limited to the ranges of 0.005% -0.1% and 0.01% -0.05%.
To increase the palatability of diet compositions containing insecticides or to extend the duration of the insecticide action, such chemicals can be microencapsulated. The process may provide a physical barrier between the drug particle and the surrounding environment, shielding the drug from interaction with taste organs or delaying digestion. Microencapsulation technology allows: controlled release of chemicals; enteric release; and taste-masking. Microencapsulation may be carried out by various methods including the use of microcapsules or microparticles that use physical or chemical barriers. Various physical methods of microecapsulation include: spray drying, spray chilling, rotary disk atomization, fluid bed coating, stationary nozzle coextrusion, centrifugal head coextrusion, submerged nozzle coextrusion and pan coating. Chemical methods of encapsulation include: phase separation, solvent extraction, interfacial polymerization, simple and complex coacervation, in-situ polymerization, liposome technology and nanoencapsulation.
Diet compositions can be placed into an uncontrolled setting by: broadcast by manual or mechanical means, spot-baiting by manual or mechanical means, incorporation into a place-pack or blister pack by manual or mechanical means, placement in a reusable or disposable bait station by manual or mechanical means or insertion into rodent burrows by manual or mechanical means.